Code transmitter receiver



June 10, 1930. c. F. JENKINS CODE TRANSMITTER RECEIVER 2 Sheets-Sheet 1 Filed March 5, 1928 June 10, 1 930. c, JENKINS I 1,763,358

CODE TRANSMITTER RECEIVER Filed March 5. 1928 2 Sheets-Sheet 2 screw, and through gear K, on shaft L, causes Patented June 10, 1930 UNITED STATES PATENT OFFICE Y omms FRANCIS JENKINS, or WASHINGTON, nIsrnIcr or conumnm, ASSIGNOR 'ro .mNxINs meoaaroams, or WASHINGTON, DISTRICT or COLUMBIA, A conrona- TION OF THE DISTRICT OF COLUMBIA TRANSMITTER RECEIVER Application filed March 5,

This invention relates to machines for electrically transmitting secret' code messages, sketches, maps, and the like, and for receiving the same by radio or by wire. 7

The advantage of this system over any heretofore practiced is that, while the sketch, map, or message is transmitted directly from a pencil or pen-ink autographed original, without coding it, and is received as an exact duplicate of the original, needing no decoding to be read at once, the same matter received by the unauthorized is illegible, for it consists of a conglomerate of dots hopelessly scrambled.

The machine employed to effect this method of secret communication may be the machine regularly employed by applicant in transmitting pencil and pen-ink sketches, with the addition of two or more other pair of contact points on the transmitter, and a correspond ing number of pen-boxes on the receivers, and a switching gear on each machine for shifting the signals.

Such shifting will create a confusion which is absolutely undecipherable to stations unacquainted with the signal-switching order.

With this and other objects in view the invention consists of the novel method and combination of parts herein disclosed, illustrated in the drawings, and more particularly pointed out in the claims.

In the drawings Figure 1 is a front view of the pen-box, drum, and switching gear assembly; Figure 2 front view of the switching gear; Figure 3 a receiving machine; Figure 4 front view of its switching gear showing wiring diagram: Figure 5 a transmitting machine; and Figure 6 front view of its switching gear showing wiring diagram.

In the drawings like symbols refer to like parts, in which A is areceiving cylinder, and B a transmitting cylinder. C, C, C" are pen-boxes, and D, D, D" two-finger transmitter contacts. E is a feed-screw, G a brush which contacts with switching gear H.

The shaft I which is driven by a motor (not shown) causes the cylinders AB to rotate. Engaging gear J in turn rotates the feed- 1928. Serial No. 259,310.

the brush G to sweep over the contact switchplates of H. I

I The paper upon which the map is to be received would be wrapped around cylinder A, ready to record in ink the incoming radio signals. The map in pencil or graphite ink to be transmitted is in the same manner wrszpped around'cylinder B. The pen-boxes C, C'. are then put in place at the left end of the cylinder for receiving the incoming radio signals; the order of the reception .by the pen-boxes depending on the wiring hook-up of the switching-gear H (shown in Figures 4 -and 6), which has three contactmembers.

At the sending station, the two-finger contacts D, D, D" are also put in a corresponding position, namely, at the left end of the transmitting cylinder.

The switching-gear hook-up can be changed daily or hourly to either of a plurality of positions, thereby enabling the friendly stations to get the desired information, while the enemy will get only a jumbled mass of dots.

The incoming radio signals, through the wires connected to screws M, M of the penbox (Figure 1), cause the pen-arm N to move to and fro. As these signals are received the pen-point O touches the paper wrapped around the receiving cylinder. impressing ink dots and strokes thereon to build up the map, sketch, or writing. A

The pen-point is normally held just clear of the paper, on the cylinder,-by the little rollers P, P, as more particularly pointed ggt in detail in application Serial No. 238,-

The operation of the device is as follows-- As'suming that the transmitting machine is carried by a scouting airship, the ship before leaving its base of operations will-have arranged a schedule 'with the receiving stafrom the transmitter. As the cylinder of the transmitter rotates, the contact-fingers short-circuit as they pass over the lines of the map, transmitting a signal representing an elementary part of that line, and which repeated with each turn of the cylinder in due course completes the line, as with all other lines.

Assuming a hand-drawn map has been made, in lead pencil or graphite ink, on a iece of paper, it is then Wrapped around and astened on the cylinder B, and a call made on all receiving stations to stand by to get it.

The transmitting machine is then started, as are all the receiving machines at stations interested, and which have a sheet of paper fastened thereon to take the map.

.Thesebroadcast signals, incoming at all receiving stations, are sent through the penboxes of the receiver, in succession, causing the pen-arm to move to and fro, applying ink to the paper, wrapped around the cylinder, leaving dots in the elementary area corresponding with that part of the message over which the contact-fingers of the transmitter have just passed. In this way the entire map is built up.

If it is arranged that the switch contactfingers shall transmit in the order 1, 2, 3, then the signals will be transmitted in that order. i i

The receiving stations knowing this order, the incoming signals switch-distributed in that order will build up a map an exact duplicate of the original.

At stations not knowing this order the record will be hopelessly unintelligible aggregation of dots only.

It is quite obvious that as elaborate a circuit-shifting switch as may be desired can be provided, and which may shift by lines or ractions of lines, as often and in such order as may be selected.

It is not believed an elaborate switching gear is necessary to be illustrated herein, the simpler switching gear shown doubtless being adequate to illustrate applicants invention.

What I claim, isv 1. The method of electrically transmitting a visual representation, which comprises dividing the representation into a plurality of sections, analysing simultaneously the successive elemental areas of each section, transmitting currents corresponding to said analysis, suspending the transmission of currents corresponding to one section, and transmitting during said suspension the currents corresponding to another section.

2. The method of electrically transmitting a visual representation, comprising simultaneously analyzing a plurality of sections of the representation, producing electric currents corresponding to each analysis, alternately transmitting said currents.

3. The method of electrically transmitting a visual representation which comprises simultaneously producing series of electric impulses, each series corresponding to a different section of the representation, and

alternately suspending the transmission of each series in an arbitrary manner.

4. In a system for electrically transmitting a visual representation, means for continuously analyzing one section of a picture to produce a corresponding continuous series of electric currents, means for transmitting said currents, means for suspending the transmission of said series, and means for transmitting another series of currents corresponding to a different section of the representation during the suspension of the first series.

5. In a system for electrically transmitting a picture, a plurality of picture analyzers, each cooperating with a different section of the picture, means for roducing electric currents under control of said analyzers, a transmission channel for said currents, and means for alternately connecting said analyzers to said channel.

6. In a system for transmitting pictures, a plurality of analyzers each associated with a dilferent section of the picture, means controlled by said analyzers for producing series of current impulses corresponding! to the elemental areas of the associated picture sections, and commutator means driven at an arbitrary speed for controlling the sequential transmission of said series.

7. In a picture transmission system the combination of a drum, a icture mounted on said drum, a plurality 0 picture analyzers each associated with difierent sections of the picture, means for rotating said drum to cause each analyzer to produce a corresponding series of electric impulses, a transmission channel, means for impressing said currents on said channel, and a commutator coupled to said drum for controlling the impression of said current series on said channel.

8. A system according to claim 7, in which the commutator is readily replaceable and is driven at an arbitrary speed.

9.- In a picture transmission system a picture to be transmitted, a plurality'of picture analyzers each associated with a diiferent section of the picture, a transmission channel, means for connecting said analyzers to said channel in arbitrary succession, and a icture receiving means comprising a plura ity of picture integrating devices and means for connecting said integrating devices to said channel in synchronism with the connection of the analyzing device.

In testimony whereof I have aflixed my signature.

- CHARLES FRANCIS JENKINS.

Ill 

